Baumgardner D.,National Autonomous University of Mexico |
Brenguier J.L.,CNRM |
Bucholtz A.,U.S. Navy |
Coe H.,University of Manchester |
And 14 more authors.
Atmospheric Research | Year: 2011
An overview is presented of airborne systems for in situ measurements of aerosol particles, clouds and radiation that are currently in use on research aircraft around the world. Description of the technology is at a level sufficient for introducing the basic principles of operation and an extensive list of references for further reading is given. A number of newer instruments that implement emerging technology are described and the review concludes with a description of some of the most important measurement challenges that remain. This overview is a synthesis of material from a reference book that is currently in preparation and that will be published in 2012 by Wiley. © 2011 Elsevier B.V.
Querel A.,Institute for Radiological Protection and Nuclear Safety |
Lemaitre P.,Institute for Radiological Protection and Nuclear Safety |
Monier M.,LaMP |
Porcheron E.,Institute for Radiological Protection and Nuclear Safety |
International Conference on Nuclear Engineering, Proceedings, ICONE | Year: 2012
The analysis of the radioactive aerosol scavenging by rain after the Chernobyl accident highlights some differences between the modelling studies and the environmental measurements. Part of this gap is due to the uncertainties on the scavenging efficiency of aerosol particles by raindrops, in particular for drops with a diameter larger than one millimeter. The IRSN (Institut de Radioprotection et de Sûreté Nucléaire) has decided to launch an experimental study to measure with a better accuracy the scavenging efficiency of large raindrops. The scavenging efficiency of aerosol has been determined by measuring precisely the mass of aerosol particles collected by a single drop after its path through an atmosphere loaded with particles. The collection efficiencies for drop diameters of 2 mm and 2.6 mm (previously unknown for atmospheric aerosols) are measured. The impact of these new data on modeling of the washout of the atmosphere by the rain is noticed. Copyright © 2012 by ASME.
Gardels D.,HDR |
McMeekin M.,Lamp |
Grate M.,City of Omaha Environmental Service |
Aurit S.,HDR |
And 2 more authors.
Pipelines 2012: Innovations in Design, Construction, Operations, and Maintenance - Doing More with Less - Proceedings of the Pipelines 2012 Conference | Year: 2012
The City of Omaha has made sustainability a priority since the inception of the Combined Sewer Overflow (CSO) Program. The development and implementation of the Long Term Control Plan (LTCP) has been guided by the City of Omaha's desire to develop a plan that meets regulatory compliance, is economically affordable, and is acceptable by the community. These three goals align with the traditional triple-bottom line analysis of sustainability that incorporates environmental stewardship, economic growth, and social progress. The City of Omaha made a decision to implement the draft version of the newly developed Envision™ Rating System on four major projects (three conveyance pipelines and one high-rate treatment facility) within the CSO Program. The focus of this paper is to describe the implementation of the rating system framework on the projects, highlight the results, and identify the lessons learned from this approach. © 2012 American Society of Civil Engineering.
Bouaziz M.,Unite de Physique des Dispositifs Semi conducteurs |
Ouerfelli J.,Unite de Physique des Dispositifs Semi conducteurs |
Srivastava S.K.,India Institute of Technology |
Bernde J.C.,LAMP |
Amlouk M.,Unite de Physique des Dispositifs Semi conducteurs
Vacuum | Year: 2011
Cu2SnS3 thin film have been synthesized by solid state reaction under vapour sulphur pressure at 530 °C, during 6 h, via a sequentially deposited copper and tin layers Cu/Sn/Cu...Sn/Cu/Sn. The structure and the composition were characterized by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Electron Probe Micro Analysis (EPMA). X-ray diffraction revealed that as the deposited film crystallizes in the cubic structure and the crystallites exhibit preferential 111 orientation of the grains. Moreover, EPMA analysis confirmed that the obtained film is stoichiometric. The SEM study shows the presence of spherical particles of ≈100-120 nm diameters. The optical absorption coefficient and band gap of the film were estimated by means of transmission and reflection optical measurements at room temperature. A relatively high absorption coefficient in the range of 104 cm-1 was indeed obtained and the band gap value is of the order of 1.1 eV. On the other hand, the electrical conductivity of Cu2SnS3 film prepared in the present experiment is suitable for fabricating a thin film solar cell based on not cheaper and environmental friendly material. © 2010 Elsevier Ltd. All rights reserved.
Benchouk K.,Oran University of Science and Technology - Mohamed Boudiaf |
Zamallach K.,Oran University of Science and Technology - Mohamed Boudiaf |
Khelil A.,Oran University of Science and Technology - Mohamed Boudiaf |
IOP Conference Series: Materials Science and Engineering | Year: 2010
Thin films of CuAlTe2 were elaborated by a sequential deposition of three elements Cu; Al and Te under secondary vacuum on glass slides followed by an annealing of 1/2 hour in an open tube within argon atmosphere. The X-rays diffraction diagram depicts a (112) preferential orientation and the presence of low intensities peaks characterizing the chalcopyrite structure. This shows that the majority of crystallites are directed towards the (112) direction with an orientation factor having an approximate value of 70 %. The height of the crystallites has been assessed using a scanning electron microscope and found to be larger than 200nm. © 2010 IOP Publishing Ltd.
Jonnalagedda M.,LAMP |
Coppey T.,DATA |
Stucki S.,LAMP |
Rompf T.,LAMP |
ACM SIGPLAN Notices | Year: 2014
Parsers are ubiquitous in computing, and many applications depend on their performance for decoding data efficiently. Parser combinators are an intuitive tool for writing parsers: tight integration with the host language enables grammar specifications to be interleaved with processing of parse results. Unfortunately, parser combinators are typically slow due to the high overhead of the host language abstraction mechanisms that enable composition. We present a technique for eliminating such overhead. We use staging, a form of runtime code generation, to dissociate input parsing from parser composition, and eliminate intermediate data structures and computations associated with parser composition at staging time. A key challenge is to maintain support for input dependent grammars, which have no clear stage distinction. Our approach applies to top-down recursive-descent parsers as well as bottom-up nondeterministic parsers with key applications in dynamic programming on sequences, where we auto-generate code for parallel hardware. We achieve performance comparable to specialized, hand-written parsers.
Mekhnache M.,Annaba University |
Drici A.,Annaba University |
Saad Hamideche L.,Annaba University |
Benzarouk H.,Annaba University |
And 4 more authors.
Superlattices and Microstructures | Year: 2011
ZnO thin films were deposited on glass, ITO (In2O3; Sn) and on ZnO:Al coated glass by spray pyrolysis. The substrates were heated at 350 °C. Structural characterization by X-ray diffraction (XRD) measurements shows that films crystallize in hexagonal structure with a preferential orientation along (0 0 2) direction. XRD peak-shift analysis revealed that films deposited on glass substrate (-0.173) were compressive, however, films deposited onto ITO (0.691) and on ZnO:Al (0.345) were tensile. Scanning electron microscopies (SEM) show that the morphologies of surface are porous in the form of nanopillars. The transmittance spectra indicated that the films of ZnO/ITO/glass and ZnO/ZnO:Al/glass exhibit a transmittance around 80% in the visible region. An empirical relationship modeled by theoretical numerical models has been presented for estimating refractive indices (n) relative to energy gap. All models indicate that the refractive index deceases with increasing energy band gap (Eg). © 2011 Elsevier Ltd. All rights reserved.
Benzarouk H.,Annaba University |
Drici A.,Annaba University |
Mekhnache M.,Annaba University |
Amara A.,Annaba University |
And 3 more authors.
Superlattices and Microstructures | Year: 2012
In the present work we studied the influence of the dopant elements and concentration on the microstructural and electrochemical properties of ZnO thin films deposited by spray pyrolysis. Transparent conductive thin films of zinc oxide (ZnO) were prepared by the spray pyrolysis process using an aqueous solution of zinc acetate dehydrate [Zn(CH 3COO) 2· 2H 2O] on soda glass substrate heated at 400 ± 5°C. AlCl 3, MgCl 2 and NiCl 2 were used as dopant. The effect of doping percentage (2-4%) has been investigated. Afterwards the samples were thermally annealed in an ambient air during one hour at 500°C. X-ray diffraction showed that films have a wurtzite structure with a preferential orientation along the (0 0 2) direction for doped ZnO. The lattice parameters a and c are estimated to be 3.24 and 5.20 , respectively. Transmission allowed to estimate the band gaps of ZnO layers. The electrochemical studies revealed that the corrosion resistance of the films depended on the concentration of dopants. © 2012 Elsevier Ltd. All rights reserved.